Segmental retaining walls are commonly used in both residential and commercial applications to create usable real estate. Fencing is often required behind such walls to reduce the potential for falls and other potential hazards. In addition, guardrails usually are required in applications where parking lots or roadways are located near top of the wall.
Fence posts typically are mounted using concrete footings. A concrete footing can be created by digging a cavity in the ground, placing a bottom portion of the fence post in the cavity, and pouring concrete into the cavity.
Segmental retaining walls often include a reinforcing tie back system. For example, multiple layers of geosynthetic soil reinforcing material (commonly referred to as “geogrid”) can be secured to the wall face so that the layers extend horizontally into the surrounding stone or soil. The interaction between the stone or soil and the reinforcing material can help to stabilize the wall face, i.e., the portion of the wall formed by stacked concrete blocks.
Digging a cavity for a fence post footing near a segmental retaining wall, after the reinforcing material has been installed, can necessitate drilling through the reinforcing material. Drilling through the reinforcing material can adversely affect the integrity of the reinforcing material, and therefore is undesirable. Hence, the cavities for fence posts located near segmental retaining walls are usually created as the wall is constructed.
In one approach, fence post cavities can be created using cylindrical cardboard forms. These forms usually are provided in relatively long lengths, and therefore must be cut to a desired length at the installation site. The form is placed on the backfill material (typically soil) used behind that wall, as the backfill material reaches a predetermined height. The predetermined height is chosen so that the top of the form is exposed from above ground after the wall has been completed, and all backfill material has been introduced and compacted. The form defines an open cavity in the ground that can receive the fence post.
The soil used as backfill material is usually kept moist, to help to achieve maximum density during compacting. Cardboard forms can be adversely affected by such moisture. Moisture from precipitation also can affect the integrity of a cardboard form. Also, the loads on the cardboard form resulting from the compacted backfill material, if excessive, can cause the form to collapse.
Alternatively, the form used to create the cavity can be created by cutting a predetermined length of polyvinyl chloride (PVC) or high-density polyethylene (HDPE) pipe. These materials are usually delivered to the installation site in ten or twenty-foot lengths. The need to cut the pipe creates an additional step in the construction process for the wall. Moreover, installers often cut the pipe using concrete demolition saws, chain saws, and other tooling not made for this particular use, thereby creating a potential safety hazard.
The cavity defined by the form creates a potential for injuries resulting from tripping over or stepping into an open hole in the ground. Moreover, the open cavity can fill with dirt and other debris, particularly in installations where fence posts will not be installed immediately after completion of the segmental retaining wall.
To reduce some of these potential issues, prior footing designs include a cover that protects the cavity. However, the cover must be removed prior to the fence post being installed. One example is discussed in U.S. Pat. No. 7,874,122 to Calle, the disclosures of which is hereby incorporated herein by reference. These covers are constantly lost on jobsites and/or create unwanted waste once removed.
A more efficient design for packaging, shipping and storage is also desired.